Fire-box for steam-boiler or other furnaces



N0 MODEL.

PATENTED FEB. 16, 1904. J. M. STRATTON.

FIRE BOX FOR STEAM BOILER OR OTHER FURNACES.

APPLIGATION FILED 1350.31, 1902.

2 SHEETS-SHEET 1.

WITNESSES:

g IIVVENTOR A TTORIVEYS 1n! mums PEPE"! co. Puomufxu, wasuwawa. u. c.

No. 752,123 PATENTED FEB. 16, 1904. J. M. STRATTON. FIRE BOX FOR STEAMBOILER OR OTHER FURNACES.

APPLIGATION'IILED DEG. 31, 1902.

N0 MODEL. 2 SHEETS-SHEET 2.

WIN/E8858 111/ vmron umwam ,%1 I BWWW W Patented February 16, 1964.

UNITED STAT S PATENT OFFICE.

JAMES MACDONALD STRATTON, OF BROOKLYN, NEW YORK.

FIRE-BOX FOR STEAM-BOILER OR OTHER FURNACES.

SPECIFICATION forming part of Letters Patent No. 752,123, dated February16, 1904.

Application filed December 31, 1902. Serial No, 137,262! (No model.)

To all whom it may concern:

Be it known that I, J AMEs MACDONALD STRATTON, a subject of the King ofGreat Britain, and a resident of Brooklyn, county of Kings, and State ofNew York, have invented certain new and useful Improvements in Fire-Boxes for Steam-Boiler or other Furnaces, of which the following is aspecification, reference being had to the accompanying drawings,

forming a part thereof, in which similar char' actors of referenceindicate corresponding parts.

This invention relates to fire boxes for steam boiler or other furnaces,the object thereof being to provide an apparatus of this characterembodying a novel construction and combination of parts so assembled asto induce uniform combustion of the fuel in the furnace and conduct theair or other medium employed to assist combustion in such a manner as toobviate liability of collapse of the furnace shell or cylinder at itscrown by reason of too rapid combustion of the fuel at the sides of thefurnace, which is frequently the case in furnaces where the draft underthe grate is not controlled, and therefore allowed to spread to thesides. To accomplish this result, I employ a longitudinally extendedchannel or chamber to conduct the air or other medium directly beneaththe central part of the grate to cause a direct draft through thecentral part of the fuel body. I

The invention will be hereinafter fully described, and specifically setforth in the annexed claims.

In the accompanying drawings, forming part of this specification, Figure1 is a longitudinal sectional elevation of part of a furnace having myimprovements embodied therein; Fig. 2 a, cross-sectional elevation takenon the line in a" of Fig. 1; Fig. 3, a longitudinal sectional elevationof a part of a furnace, illustrating a slight structural modification ofmy invention; and Fig. 4 is a cross-sectional elevation taken on theline y y of Fig. 3.

In the, practice of my invention as illustrated by Figs. 1 and 2 of thedrawings I have illustrated the device in connection with a part of afurnace of ordinary construction com- 5 prising the cylindrical fire boxA, grate B,

ash-pit O, and air-box D of the ordinary character employed Where aninduced current of air or other medium is used. This air-box has aninlet-tube 0, leading through the side thereof, which is adapted forattachment with a blower or other suitable source of supply, and anoutlet-portc' leads therefrom into an air-chamberE, located within theash-pit at the forward end. This chamber E has an outlet-portc, whichcommunicates with a port f, leading through the front wall of theair-con.- ducting channel F, which comprises the easing F, embodying theside walls 1 1 and end walls 2 2 and the trough F. This said airchannelis located within the ash-pit upon a horizontal line beneath the grate,and the side walls extend upwardly beneath the grate-bars, the end wallsconforming to the shape of the bridges supporting the grate-bars,whereby the draft is forced directly up through the central part of thegrate and brought into direct contact with the central part of the massof fuel to facilitate combustion at the center and prevent unduecombustion at the sides, which generally occurs when the draft isallowed to spread to the sides of the cylinder forming thefurnace-walls.

To admit of cleaning the ashes from the trough F and also to control thedraft, if desirable, an opening f and damper Or are provided. Thisopening is formed through the front walls of said trough, and it isnormally closed by means of the damper G; but it may be opened or partlyopened, if found desirable, to allow a material draft to enter thechannel F.

In the construction illustrated by Figs. 3 and 4 of the drawings theair-channel comprises longitudinal plates H H, extended longitudinallythrough the fire-box and hinged, as at it, whereby they may be swung toeither the right or left to expand or contract the outlet of thechannel, so that the outlet of the channel may be arranged in properrelative arrangement with the bottom of the grate. The plates H haveauxiliary vertically-adjustable plates H connected thereto by means ofbolts I and nuts 2 the bolts passing through slots h in the plates H,These last-named plates may he slipped as far as the length of the slotsh, and thereby made to regulate the amount of air admitted from theair-channel into the ash-pit. In this construction the induced draft issupplied through the medium of the air-box D, which communicates with aninlet-port 0 in the front of the ash-pit.

In the operation of the invention the draft of air or other medium beingsupplied and conducted directly beneath the central part of the mass offuel causes uniform combustion within the fire-box of the furnace andprevents the side spread of the draft and consequent too rapid sidecombustion of the fuel, which causes the flames to unduly heat thefurnace-cylinder at its sides and near the dome, which frequently, owingto rapid expansion and contraction of the plates forming the cylinder,causes collapse.

I do not confine myself to the specific details of mechanicalconstruction, proportion, conformation, and relative arrangement of theparts as herein shown and described, as it is obvious that under thescope of my invention I am entitled to structural variations necessaryto applying my invention to various styles of furnaces.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is

. 1. In a draft-controlling means, the combination with a fire-boxcomprising side walls,

a grate, an ash-pit and an air-box; of an airchannel having end walls,side walls and a bottom, located in said fire-box directly under themiddle of said grate and opening thereinto, a conduit communicating withsaid airboX and having an inlet leading into said channel, a damper insaid inlet, and adamper door T ing combustion from said air-box to saidairchannel and said grate, and dampers arranged to control the flow ofsuch media into said channel and to said grate.

In testimony that I claim the foregoing as my invention I have signed myname, in presence of two witnesses, this 23d day of December, 1902.

JAMES MACDONALD STRATTON.

Witnesses:

B. PATTERSON, c S. M. STONE.

